Clapper valve

ABSTRACT

A valve assembly adapted for use in oil and gas operations. In one aspect, the valve assembly includes a valve body defining an internal region, an inlet passageway, and an outlet passageway, the inlet and outlet passageways extending into the internal region; a valve seat connected to the valve body and defining a fluid passageway; a clapper extending within the internal region and defining an annular groove; and a seal extending within the annular groove of the clapper and adapted to sealingly engage the valve seat. In an example embodiment, the clapper is actuable between an open configuration, in which fluid flow is permitted through the fluid passageway; and a closed configuration, in which the seal sealingly engages the valve seat to at least partially restrict fluid flow through the fluid passageway.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of the filing date of, and priorityto, U.S. Application No. 62/294,019, filed Feb. 11, 2016, the entiredisclosure of which is hereby incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates in general to valves and, in particular,to clapper valves used in oil or gas operations.

BACKGROUND OF THE DISCLOSURE

In oil or gas operations, such as, for example, the fracturing or gravelpacking of a subterranean wellbore, a clapper valve may be used tocontrol the flow of fracturing and/or gravel-packing fluids. A clappervalve permits fluid flow in a first direction, but prevents, or at leastreduces, fluid flow in a second direction, which is generally oppositethe first direction. Any vibration caused by, for example, turbulence inthe flow of fluid through the clapper valve, often produces significantwear to the internal components of the clapper valve. Moreover, theeffectiveness of the clapper valve in preventing, or at least reducing,fluid flow in the second direction is often diminished as a result ofimproper alignment and/or excessive loading of the internal componentsof the clapper valve. Such issues typically cause prematuredeterioration of the clapper valve. Therefore, what is needed is anapparatus, system, assembly, or method to address one or more of theforegoing issues, and/or one or more other issues.

SUMMARY

In a first aspect, there is provided a valve assembly, including a valvebody defining an internal region, an inlet passageway, and an outletpassageway, the inlet and outlet passageways extending into the internalregion; a valve seat connected to the valve body and defining a fluidpassageway, the valve seat including a first end face extending aboutthe fluid passageway; a clapper extending within the internal region,the clapper including a second end face, an exterior surface, and anannular groove formed in the second end face and the exterior surface;and a seal extending within the annular groove of the clapper andadapted to sealingly engage the first end face of the valve seat.

In an example embodiment, the clapper is actuable between an openconfiguration, in which fluid flow is permitted through the fluidpassageway in a first direction; and a closed configuration, in which atleast the seal and the second end face contact the first end face to atleast partially restrict fluid flow through the fluid passageway in asecond direction, which is opposite the first direction.

In another example embodiment, the contact between the first and secondend faces limits compression of the seal against the first end face.

In yet another example embodiment, the seal includes polyurethane.

In certain example embodiments, the valve body further defines an accessbore intersecting the internal region, and the valve assembly furtherincludes a hanger supported within the access bore, the clapper beingconnected to the hanger and pivotable between the open configuration andthe closed configuration.

In an example embodiment, the seal includes an annular bulbousprotrusion; and a radially-extending contact surface adapted to contactthe first end face, the radially-extending contact surface being axiallyoffset from the second end face.

In another example embodiment, the seal further includes an annularconcave surface axially between the exterior surface of the clapper andthe annular bulbous protrusion.

In yet another example embodiment, at the annular groove, the clapperincludes first and second annular rounds and a concave surface, thefirst annular round adjoining the exterior surface, the second annularround adjoining the second end face, and the concave surface adjoiningthe first and second annular rounds.

In certain example embodiments, the first annular round is axiallyoffset from the second end face to permit radial expansion of the seal.

In an example embodiment, the seal is bonded to at least one of: thefirst annular round, the second annular round, and/or the concavesurface.

In a second aspect, there is provided a valve assembly, including avalve body defining an internal region, inlet and outlet passagewaysintersecting the internal region, and an access bore intersecting theinternal region, the valve body including an internal shoulder at theaccess bore; a hanger supported within the access bore on the internalshoulder, the hanger defining first and second tapered slots, the firstand second tapered slots each defining first and second end portions,the first and second end portions having first and second internaldimensions, respectively, the first internal dimension being less thanthe second internal dimension; a valve seat connected to the valve body,the valve seat defining a fluid passageway; and a clapper pivotablyconnected to the hanger via a pin extending within the first and secondtapered slots.

In an example embodiment, the clapper is actuable between an openconfiguration, in which fluid flow is permitted through the fluidpassageway in a first direction; and a closed configuration, in whichthe clapper is seated against the valve seat to at least partiallyrestrict fluid flow through the fluid passageway in a second direction,which is opposite the first direction.

In another example embodiment, when the clapper is in the openconfiguration, the pin is urged toward the respective first end portionsof the first and second tapered slots, thus minimizing vertical movementand/or horizontal movement of the pin relative to the hanger as a resultof the first internal dimension being less than the second internaldimension.

In yet another example embodiment, when the clapper is in the closedconfiguration, the pin is urged toward the respective second endportions of the first and second tapered slots, thus permitting verticalmovement and/or horizontal movement of the pin relative to the hanger asa result of the second internal dimension being greater than the firstinternal dimension.

In certain example embodiments, the hanger includes first and secondhinge blocks within which the respective first and second tapered slotsare formed.

In an example embodiment, the clapper includes a third hinge blockextending between the first and second hinge blocks, the third hingeblock defining a cylindrical passage within which the pin also extends.

In a third aspect, there is provided a valve assembly, including a valvebody defining an internal region, inlet and outlet passagewaysintersecting the internal region, and an access bore intersecting theinternal region, the valve body including an internal shoulder at theaccess bore; a hanger supported within the access bore on the internalshoulder; a cap connected to the valve body at the access bore; abiasing member positioned between the cap and the hanger, the biasingmember urging the hanger into engagement, or near engagement, with theinternal shoulder of the valve body; a valve seat connected to the valvebody, the valve seat defining a fluid passageway; and a clapperpivotably connected to the hanger.

In an example embodiment, the biasing member prevents, or at leastreduces, vibration and wear of the hanger and/or the clapper.

In another example embodiment, the clapper is actuable between an openconfiguration, in which fluid flow is permitted through the fluidpassageway in a first direction; and a closed configuration, in whichthe clapper is seated against the valve seat to at least partiallyrestrict fluid flow through the fluid passageway in a second direction,which is opposite the first direction.

In yet another example embodiment, the hanger includes an externalshoulder against which the biasing member is constrained.

In certain example embodiments, the hanger includes an external lip, andthe biasing member urges the external lip into engagement, or nearengagement, with the internal shoulder of the valve body.

In a fourth aspect, there is provided a kit which, when assembled, formsa valve assembly, the kit including a valve body defining an internalregion, inlet and outlet passageways intersecting the internal region,and a counterbore; a valve seat defining an external annular groove, thevalve seat being adapted to be removably engaged with the valve body atthe counterbore; and an annular seal extending within the externalannular groove and adapted to sealingly engage the valve body when thevalve seat is removably engaged with the valve body, the annular sealbeing twist-resistant so that, when relative motion is effected betweenthe valve seat and the valve body, distortion of the annular seal isprevented, or at least reduced.

In an example embodiment, the valve body includes an internal threadedconnection at the counterbore, and the valve seat includes an externalthreaded connection adapted to be threadably engaged with the internalthreaded connection in response to relative rotation between the valveseat and the valve body.

In another example embodiment, the annular seal facilitates face-to-facecontact, rather than point contact, between the annular seal and thevalve body.

In yet another example embodiment, the annular seal has a rectangularcross-section.

In certain example embodiments, the kit further includes a clapperadapted to extend within the internal region and to be actuable betweenan open configuration, in which fluid flow is permitted through thefluid passageway in a first direction; and a closed configuration, inwhich the clapper is seated against the valve seat to at least partiallyrestrict fluid flow through the fluid passageway in a second direction,which is opposite the first direction.

In a fifth aspect, there is provided a valve assembly, including a valvebody defining an internal region, an inlet passageway, and an outletpassageway, the inlet and outlet passageways extending into the internalregion; a valve seat connected to the valve body and defining a fluidpassageway, the valve seat including a first end face extending aboutthe fluid passageway; a clapper extending within the internal region,the clapper including a second end face and an annular groove formed inthe second end face; and a seal extending within the annular groove ofthe clapper and adapted to sealingly engage the first end face, the sealincluding polyurethane; wherein the clapper is actuable between an openconfiguration, in which fluid flow is permitted through the fluidpassageway in a first direction, and a closed configuration, in which atleast the seal and the second end face contact the first end face to atleast partially restrict fluid flow through the fluid passageway in asecond direction, which is opposite the first direction.

In an example embodiment, the contact between the first and second endfaces limits compression of the seal against the first end face.

In another example embodiment, the clapper further includes acircumferentially-extending exterior surface at least partially definingthe annular groove.

In a sixth aspect, there is provided a valve member adapted to be seatedagainst a valve seat that defines a fluid passageway, the valve memberincluding a body including an end face, an exterior surface, and anannular groove formed in the end face and the exterior surface; and aseal extending within the annular groove of the body and adapted tosealingly engage the valve seat; wherein the valve member is actuablebetween an open configuration, in which fluid flow is permitted throughthe fluid passageway in a first direction, and a closed configuration,in which the valve member is seated against the valve seat to at leastpartially restrict fluid flow through the fluid passageway in a seconddirection, which is opposite the first direction.

In an example embodiment, when the valve member is in the closedconfiguration, at least the seal and the end face are in contact thevalve seat.

In another example embodiment, the contact between the end face and thevalve seat limits compression of the seal against the valve seat.

In yet another example embodiment, the seal includes polyurethane.

In certain example embodiments, the seal includes an annular bulbousprotrusion; and a radially-extending contact surface axially offset fromthe end face and adapted to contact the valve seat when the valve memberis in the closed configuration.

In an example embodiment, the seal further includes an annular concavesurface axially between the exterior surface of the valve member and theannular bulbous protrusion.

In another example embodiment, at the annular groove, the body includesfirst and second annular rounds and a concave surface, the first annularround adjoining the exterior surface, the second annular round adjoiningthe end face, and the concave surface adjoining the first and secondannular rounds.

In yet another example embodiment, the first annular round is axiallyoffset from the end face to permit radial expansion of the seal.

In certain example embodiments, the seal is bonded to at least one of:the first annular round, the second annular round, and/or the concavesurface.

In a seventh aspect, there is provided a kit which, when assembled,forms a valve assembly, the kit including a valve body defining aninternal region, an inlet passageway, and an outlet passageway, theinlet and outlet passageways extending into the internal region; a valveseat adapted to be connected to the valve body and defining a fluidpassageway, the valve seat including a first end face extending aboutthe fluid passageway; a clapper adapted to extend within the internalregion, the clapper including a second end face, an exterior surface,and an annular groove formed in the second end face and the exteriorsurface; and a seal extending within the annular groove of the clapperand adapted to sealingly engage the first end face of the valve seat.

In an example embodiment, the clapper is adapted to be actuable betweenan open configuration, in which fluid flow is permitted through thefluid passageway in a first direction; and a closed configuration, inwhich at least the seal and the second end face contact the first endface to at least partially restrict fluid flow through the fluidpassageway in a second direction, which is opposite the first direction.

In another example embodiment, when the second end face contacts thefirst end face, the contact between the first and second end faceslimits compression of the seal against the first end face.

In yet another example embodiment, the seal includes polyurethane.

In certain example embodiments, the valve body further defines an accessbore intersecting the internal region, and the valve assembly furtherincludes a hanger supported within the access bore, the clapper beingadapted to be connected to the hanger and pivotable between the openconfiguration and the closed configuration.

In an example embodiment, the seal includes an annular bulbousprotrusion; and a radially-extending contact surface adapted to contactthe first end face, the radially-extending contact surface being axiallyoffset from the second end face.

In another example embodiment, the seal further includes an annularconcave surface axially between the exterior surface of the clapper andthe annular bulbous protrusion.

In yet another example embodiment, at the annular groove, the clapperincludes first and second annular rounds and a concave surface, thefirst annular round adjoining the exterior surface, the second annularround adjoining the second end face, and the concave surface adjoiningthe first and second annular rounds.

In certain example embodiments, the first annular round is axiallyoffset from the second end face to permit radial expansion of the seal.

In an example embodiment, the seal is bonded to at least one of: thefirst annular round, the second annular round, and/or the concavesurface.

In an eighth aspect, there is provided a kit which, when assembled,forms a valve assembly, the kit including a valve body defining aninternal region, inlet and outlet passageways intersecting the internalregion, and an access bore intersecting the internal region, the valvebody including an internal shoulder at the access bore; a hanger adaptedto be supported within the access bore on the internal shoulder, thehanger defining first and second tapered slots, the first and secondtapered slots each defining first and second end portions, the first andsecond end portions having first and second internal dimensions,respectively, the first internal dimension being less than the secondinternal dimension; a valve seat adapted to be connected to the valvebody, the valve seat defining a fluid passageway; and a clapper adaptedto be pivotably connected to the hanger via a pin extending within thefirst and second tapered slots.

In an example embodiment, the clapper is adapted to be actuable betweenan open configuration, in which fluid flow is permitted through thefluid passageway in a first direction; and a closed configuration, inwhich the clapper is seated against the valve seat to at least partiallyrestrict fluid flow through the fluid passageway in a second direction,which is opposite the first direction.

In another example embodiment, when the clapper is in the openconfiguration, the pin is urged toward the respective first end portionsof the first and second tapered slots, thus minimizing vertical movementand/or horizontal movement of the pin relative to the hanger as a resultof the first internal dimension being less than the second internaldimension.

In yet another example embodiment, when the clapper is in the closedconfiguration, the pin is urged toward the respective second endportions of the first and second tapered slots, thus permitting verticalmovement and/or horizontal movement of the pin relative to the hanger asa result of the second internal dimension being greater than the firstinternal dimension.

In certain example embodiments, the hanger includes first and secondhinge blocks within which the respective first and second tapered slotsare formed.

In an example embodiment, the clapper includes a third hinge blockadapted to extend between the first and second hinge blocks, the thirdhinge block defining a cylindrical passage within which the pin alsoextends.

In a ninth aspect, there is provided a kit which, when assembled, formsa valve assembly, the kit including a valve body defining an internalregion, inlet and outlet passageways intersecting the internal region,and an access bore intersecting the internal region, the valve bodyincluding an internal shoulder at the access bore; a hanger adapted tobe supported within the access bore on the internal shoulder; a capadapted to be connected to the valve body at the access bore; a biasingmember adapted to be positioned between the cap and the hanger to urgethe hanger into engagement, or near engagement, with the internalshoulder of the valve body; a valve seat adapted to be connected to thevalve body, the valve seat defining a fluid passageway; and a clapperadapted to be pivotably connected to the hanger.

In an example embodiment, when the biasing member is positioned betweenthe cap and the hanger, the biasing member prevents, or at leastreduces, vibration and wear of the hanger and/or the clapper.

In another example embodiment, the clapper is adapted to be actuablebetween an open configuration, in which fluid flow is permitted throughthe fluid passageway in a first direction; and a closed configuration,in which the clapper is seated against the valve seat to at leastpartially restrict fluid flow through the fluid passageway in a seconddirection, which is opposite the first direction.

In yet another example embodiment, the hanger includes an externalshoulder against which the biasing member is adapted to be constrained.

In certain example embodiments, the hanger includes an external lip, andthe biasing member is adapted to urge the external lip into engagement,or near engagement, with the internal shoulder of the valve body.

In a tenth aspect, there is provided a kit which, when assembled, formsa valve assembly, the kit including a valve body defining an internalregion, an inlet passageway, and an outlet passageway, the inlet andoutlet passageways extending into the internal region; a valve seatadapted to be connected to the valve body and defining a fluidpassageway, the valve seat including a first end face extending aboutthe fluid passageway; a clapper adapted to extend within the internalregion, the clapper including a second end face at least partiallydefining an annular groove; and a seal extending within the annulargroove of the clapper and adapted to sealingly engage the first endface, the seal including polyurethane; wherein the clapper is adapted tobe actuable between an open configuration, in which fluid flow ispermitted through the fluid passageway in a first direction, and aclosed configuration, in which at least the seal and the second end facecontact the first end face to at least partially restrict fluid flowthrough the fluid passageway in a second direction, which is oppositethe first direction.

In an example embodiment, when the second end face contacts the firstend face, the contact between the first and second end faces limitscompression of the seal against the first end face.

In another example embodiment, the clapper further includes acircumferentially-extending exterior surface at least partially definingthe annular groove.

In an eleventh aspect, there is provided an apparatus, including a valvemember including an end face, an exterior surface, and an annular grooveformed in the end face and/or the exterior surface; and a seal adaptedto extend within the annular groove, the seal including an annularbulbous protrusion; and a radially-extending contact surface axiallyoffset from the end face of the valve member, the radially-extendingcontact surface being adapted to contact a valve seat when the valvemember is in a closed configuration.

In an example embodiment, the seal further includes an annular concavesurface axially between the exterior surface of the valve member and theannular bulbous protrusion.

In a twelfth aspect, there is provided a valve assembly including avalve body defining an internal region, an inlet passageway, and anoutlet passageway, the inlet and outlet passageways extending into theinternal region; a valve seat connected to the valve body and defining afluid passageway, the valve seat including a first end face extendingabout the fluid passageway; a clapper extending within the internalregion, the clapper including a second end face at least partiallydefining a first annular groove; and a seal extending within the firstannular groove and adapted to sealingly engage the first end face of thevalve seat; wherein the clapper is actuable between: an openconfiguration, in which fluid flow is permitted through the fluidpassageway; and a closed configuration, in which the seal sealinglyengages the first end face to at least partially restrict fluid flowthrough the fluid passageway.

In an example embodiment, when the clapper is in the closedconfiguration, the second end face contacts the first end face to limitcompression of the seal against the first end face.

In another example embodiment, the clapper further includes acircumferentially-extending exterior surface at least partially definingthe first annular groove.

In yet another example embodiment, the seal includes an annular bulbousprotrusion and a radially-extending contact surface adapted to contactthe first end face when the clapper is in the closed configuration, theradially-extending contact surface being axially offset from the secondend face.

In certain example embodiments, at the first annular groove, the clapperincludes first and second annular rounds and a concave surface, thefirst annular round adjoining the exterior surface and being axiallyoffset from the second end face to permit radial expansion of the seal,the second annular round adjoining the second end face, and the concavesurface adjoining the first and second annular rounds.

In an example embodiment, the valve body further defines an access boreextending into the internal region; and the valve assembly furtherincludes a hanger extending within the access bore, the clapper beingpivotably coupled to the hanger so as to be pivotable between the openconfiguration and the closed configuration.

In another example embodiment, the hanger defines first and secondtapered slots, the first tapered slot defining first and second endportions, the second tapered slot defining third and fourth endportions, the first and third end portions each having a first internaldimension, and the second and fourth end portions each having a secondinternal dimension, wherein the first internal dimension is less thanthe second internal dimension.

In yet another example embodiment, the hanger includes first and secondhinge blocks, the first tapered slot being formed in the first hingeblock, and the second tapered slot being formed in the second hingeblock; the clapper includes a third hinge block extending between thefirst and second hinge blocks, the third hinge block defining acylindrical passage; and the valve assembly further includes a pinextending within the first and second tapered slots and the cylindricalpassage.

In certain example embodiments, when the clapper is in the openconfiguration, the pin is urged toward the first and third end portionsof the first and second tapered slots, respectively, such that the pinis at least partially restricted from moving one or more of verticallyor horizontally relative to the hanger.

In an example embodiment, when the clapper is in the closedconfiguration, the pin is urged toward the second and fourth endportions of the first and second tapered slots, respectively, to enablethe pin to at least partially move one or more of vertically orhorizontally relative to the hanger.

In another example embodiment, the valve body includes an internalshoulder at the access bore; and the valve assembly further includes acap coupled to the valve body at the access bore and a biasing memberpositioned between the cap and the hanger, the biasing member urging thehanger towards the internal shoulder of the valve body.

In yet another example embodiment, the valve body further defines acounterbore and the valve seat further defines a second annular groove,the valve seat being adapted to be removably engaged with the valve bodyat the counterbore; and an annular seal extends within the secondannular groove and is adapted to sealingly engage a portion of the valvebody when the valve seat is removably engaged with the valve body, theannular seal being configured to reduce a force imparted on the annularseal when relative motion is effected between the valve seat and thevalve body.

In certain example embodiments, to promote face-to-face contact betweenthe annular seal and the valve body, the annular seal includes a sealingface extending substantially parallel to the portion of the valve bodywith which the annular seal is adapted to be sealingly engaged.

In a thirteenth aspect, there is provided a valve member adapted to beseated against a valve seat that defines a fluid passageway, the valvemember including a body including an end face at least partiallydefining an annular groove; and a seal extending within the annulargroove of the body and adapted to sealingly engage the valve seat;wherein the valve member is actuable between: an open configuration, inwhich fluid flow is permitted through the fluid passageway; and a closedconfiguration, in which the seal sealingly engages the valve seat to atleast partially restrict fluid flow through the fluid passageway.

In an example embodiment, when the valve member is in the closedconfiguration, the end face contacts the valve seat to limit compressionof the seal against the valve seat.

In another example embodiment, the body further includes acircumferentially-extending exterior surface at least partially definingthe annular groove.

In yet another example embodiment, the seal includes an annular bulbousprotrusion and a radially-extending contact surface adapted to contactthe valve seat when the valve member is in the closed configuration, theradially-extending contact surface being axially offset from the endface.

In certain example embodiments, the seal further includes an annularconcave surface axially between the exterior surface of the valve memberand the annular bulbous protrusion.

In an example embodiment, at the annular groove, the body includes firstand second annular rounds and a concave surface, the first annular roundadjoining the exterior surface, the second annular round adjoining theend face, and the concave surface adjoining the first and second annularrounds.

In another example embodiment, the first annular round is axially offsetfrom the end face to permit radial expansion of the seal.

Other aspects, features, and advantages will become apparent from thefollowing detailed description when taken in conjunction with theaccompanying drawings, which are a part of this disclosure and whichillustrate, by way of example, principles of the embodiments disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present disclosure will be understood morefully from the detailed description given below and from theaccompanying drawings of various embodiments of the disclosure. In thedrawings, like reference numbers may indicate identical or functionallysimilar elements.

FIG. 1A is a perspective view of a clapper valve, the clapper valveincluding a valve body, a valve seat, a hanger, a clapper, and a cap,according to an example embodiment.

FIG. 1B is a cross-sectional view of the clapper valve of FIG. 1A, takenalong line 1B-1B of FIG. 1A, according to an example embodiment.

FIG. 2A is a perspective view of the hanger of FIGS. 1A and 1B,according to an example embodiment.

FIG. 2B is an elevational view of the hanger of FIGS. 1A, 1B, and 2A,according to an example embodiment.

FIG. 2C is a cross-sectional view of the hanger of FIGS. 1A, 1B, 2A, and2B, taken along line 2C-2C of FIG. 2B, according to an exampleembodiment.

FIG. 2D is an enlarged cross-sectional view depicting a portion of thehanger of FIG. 2C, according to an example embodiment.

FIG. 3A is a perspective view of the clapper of FIGS. 1A and 1B,according to an example embodiment.

FIG. 3B is an elevational view of the clapper of FIGS. 1A, 1B, and 3A,according to an example embodiment.

FIG. 3C is a cross-sectional view of the clapper of FIGS. 1A, 1B, 3A,and 3B, taken along line 3C-3C of FIG. 3B, according to an exampleembodiment.

FIG. 3D is an enlarged cross-sectional view depicting a portion of theclapper of FIG. 3C, according to an example embodiment.

FIG. 4A is a cross-sectional view of the clapper valve of FIGS. 1A, 1B,2A-2D, and 3A-3D in an assembled state, according to an exampleembodiment.

FIG. 4B is an enlarged cross-sectional view depicting a portion of theclapper valve of FIG. 4A, according to an example embodiment.

FIG. 4C is an enlarged cross-sectional view depicting another portion ofthe clapper valve of FIG. 4A, according to an example embodiment.

FIG. 5A is an elevational view of the clapper valve of FIGS. 1A, 1B,2A-2D, 3A-3D, and 4A-4C in an open configuration, including the valveseat, the hanger, the clapper, and the cap, but omitting the valve body,according to an example embodiment.

FIG. 5B is an enlarged elevational view depicting a portion of theclapper valve of FIG. 5A in the open configuration, according to anexample embodiment.

FIG. 6A is an elevational view of the clapper valve of FIGS. 1A, 1B,2A-2D, 3A-3D, and 4A-4C in a closed configuration, including the valveseat, the hanger, the clapper, and the cap, but omitting the valve body,according to an example embodiment.

FIG. 6B is an enlarged elevational view depicting a portion of theclapper valve of FIG. 6A in the closed configuration, according to anexample embodiment.

DETAILED DESCRIPTION

Referring initially to FIGS. 1A and 1B, an example embodiment of aclapper valve, generally referred to by the reference numeral 10, isillustrated. The clapper valve 10 includes a valve body 12; a valve seat14 connected to the valve body 12; a hanger 16 extending within thevalve body 12 proximate the valve seat 14; a clapper 18 pivotablyconnected to the hanger 16 and actuable between an open configuration,in which fluid flow is permitted through the valve body 12, and a closedconfiguration, in which the clapper 18 is seated against the valve seat14 to at least partially restrict fluid flow through the valve body 12;and a cap 20 connected to the valve body 12 to secure the hanger 16 inposition relative to the valve seat 14. The clapper valve 10 is adaptedto be incorporated into a flowline through which fluid ordinarily flowsin an axial direction 22. Accordingly, the valve body 12 includes aninlet end 24 and an outlet end 26. A pair of flowline connectors 28 aand 28 b are associated with the inlet and outlet ends 24 and 26,respectively, of the valve body 12. The flowline connectors 28 a and 28b are adapted to couple the valve body 12 in the flowline so that fluidflow through the valve body 12 is permitted in the axial direction 22and prevented, or at least reduced, in an axial direction 30, which isopposite the axial direction 22.

In several example embodiments, at least one of the flowline connectors28 a and 28 b is a male half of a hammer union. In several exampleembodiments, at least one of the flowline connectors 28 a and 28 b is afemale half of a hammer union. As shown in FIGS. 1A and 1B, in anexample embodiment, the flowline connector 28 a is a female half of ahammer union, and the flowline connector 28 b is a male half of a hammerunion. In several example embodiments, at least one of the flowlineconnectors 28 a and 28 b is, includes, or is part of another type offlowline connector having components that are not associated with ahammer union, such as, for example, components associated with ahammerless union, flanges, fasteners, welds, clamps, other components,or any combination thereof.

As shown in FIG. 1B, the valve body 12 includes an internal region 32within which at least respective portions of the valve seat 14, thehanger 16, and the clapper 18 extend. The valve body 12 further includesinlet and outlet passageways 34 and 36 intersecting the internal region32. In several example embodiments, the inlet passageway 34 and theoutlet passageway 36 extend substantially co-axially along an axis 38.An internal shoulder 40 is formed at the junction between the internalregion 32 and the inlet passageway 34, facing generally in the axialdirection 22. In several example embodiments, the internal shoulder 40lies in a plane that is substantially perpendicular to the axis 38. Acounterbore 42 is formed in the internal shoulder 40. The counterbore 42extends from the internal shoulder 40 in the axial direction 30, thusincluding a counterbore shoulder 44 in the valve body 12. Thecounterbore shoulder 44 faces generally in the axial direction 22.Moreover, in several example embodiments, the counterbore shoulder 44lies in a plane that is substantially perpendicular to the axis 38. Aninternal threaded connection 46 is formed in the valve body 12 at thecounterbore 42. In several example embodiments, a generally cylindricalsurface 48 is formed in the interior of the valve body 12, axiallybetween the internal threaded connection 46 and the counterbore shoulder44.

An access bore 50 is formed in the valve body 12 and intersects theinternal region 32. In several example embodiments, the access bore 50extends along an axis 52 that is substantially perpendicular to the axis38 of the inlet and outlet passageways 34 and 36. An internal threadedconnection 54 is formed in the valve body 12 at the access bore 50.Moreover, the access bore 50 includes an internal shoulder 56 in thevalve body 12, facing generally toward the internal threaded connection54. In several example embodiments, the internal shoulder 56 lies in aplane that is substantially perpendicular to the axis 52. In severalexample embodiments, a generally cylindrical surface 57 is formed in theinterior of the valve body 12, axially between the internal threadedconnection 54 and the internal shoulder 56. The internal shoulder 56includes a ledge 58 along a side of the internal shoulder 56 adjacentthe counterbore 42. The ledge 58 has a greater width or radial dimensionrelative to the axis 52 than the remainder of the internal shoulder 56.The width or radial dimension of the ledge 58 is the distance, along aradial line intersecting the axis 52, between the sidewall of the accessbore 50 and an edge 60 of the ledge 58. The edge 60 of the ledge 58defines a straight profile. In several example embodiments, the edge 60of the ledge 58 lies perpendicular to, or substantially perpendicularto, the axis 38 of the inlet and outlet passageways 34 and 36.Alternatively, the edge 60 of the ledge 58 may define a curvilinearprofile. One or more openings 62 extends through the ledge 58 into theinternal region 32. In several example embodiments, at least one of theopenings 62 are threaded holes.

The valve seat 14 includes opposing end faces 14 a and 14 b. A fluidpassageway 64 extends through the valve seat 14 along an axis 66, whichaxis 66 is substantially co-axial with the axis 38. In several exampleembodiments, the end faces 14 a and 14 b lie in a plane that issubstantially perpendicular to the axis 66. The valve seat 14 includes aflange 68 formed in the exterior thereof, proximate the end face 14 a.The flange 68 includes the end face 14 a of the valve seat 14 and anexternal shoulder 70 that faces generally in the axial direction 30. Inseveral example embodiments, the external shoulder 70 lies in a planethat is substantially perpendicular to the axis 66. An external annularrecess 72 is formed in the flange 68, axially between the end face 14 aand the external shoulder 70. The external annular recess 72 is adaptedto be aligned with the one or more openings 62 in the ledge 58. Thevalve seat 14 also includes an external threaded connection 74 extendingaxially between the external shoulder 70 and the end face 14 b. Theexternal threaded connection 74 of the valve seat 14 is adapted to bethreadably engaged with the internal threaded connection 46 of the valvebody 12. In several example embodiments, an external annular groove 76is formed in the valve seat 14, axially between the external threadedconnection 74 and the end face 14 b.

The cap 20 includes opposing end portions 20 a and 20 b and an externalthreaded connection 78 extending axially between the end portions 20 aand 20 b. The external threaded connection 78 of the cap 20 is adaptedto be connected to the internal threaded connection 54 of the valve body12. Further, the cap 20 includes an end face 80 at the end portion 20 bthereof. An external annular groove 82 is formed in the cap 20, axiallybetween the external threaded connection 78 and the end face 80. The cap20 is adapted to secure the hanger 16 and the clapper 18 within thevalve body 12 when the external threaded connection 78 of the cap 20 isthreadably engaged with the internal threaded connection 54 of the valvebody 12, as will be discussed in further detail below. In severalexample embodiments, the internal threaded connection 54 of the valvebody 12 and the external threaded connection 78 of the cap 20 areomitted or are replaced by other connections utilizing, for example,flanges, fasteners, welds, clamps, or the like.

Referring to FIGS. 2A-2D, with continuing reference to FIGS. 1A and 1B,an example embodiment of the hanger 16 is illustrated. The hanger 16includes a generally disk-shaped annular body 84 extending about acentral axis 86. The annular body 84 includes a central opening 88 andopposing end faces 84 a and 84 b. An external lip 89 is formed in theperiphery of the annular body 84, facing generally in an axial direction90 (as shown in FIG. 2C). In several example embodiments, the externallip 89 lies in a plane that is substantially perpendicular to thecentral axis 86. The external lip 89 is offset in an axial direction 92,which is opposite the axial direction 90, from the end face 84 b of theannular body 84.

A segment 94 of the external lip 89 has a greater width or radialdimension relative to the central axis 86 than the remainder of theexternal lip 89. The width or radial dimension of the segment 94 is thedistance, along a radial line intersecting the central axis 86, betweenthe outer periphery of the annular body 84 and an edge 96 of the segment94. The edge 96 of the segment 94 defines a straight profile. In severalexample embodiments, the edge 96 of the segment 94 is adapted to lieperpendicular to, or substantially perpendicular to, the axis 38 of theinlet and outlet passageways 34 and 36. Alternatively, the edge 96 ofthe segment 94 may define a curvilinear profile. In any event, thesegment 94 has approximately the same radial dimension and shape as theledge 58 of the valve body 12. One or more openings 98 are formedthrough the segment 94 of the annular body 84. In several exampleembodiments, at least one of the openings 98 is aligned with theopenings 62 in the ledge 58. A wall portion 100 including opposing endportions 100 a and 100 b borders the segment 94 along the edge 96. Thewall portion 100 is adapted to abut, or nearly abut, the edge 60 of theledge 58 to act as an anti-rotation device for the hanger 16 within thevalve body 12.

An external shoulder 102 is also formed in the periphery of the annularbody 84, facing generally in the axial direction 92. In several exampleembodiments, the external shoulder 102 lies is a plane that issubstantially perpendicular to the central axis 86. The externalshoulder 102 is offset in the axial direction 90 from the end face 84 aof the annular body 84. The annular body 84 further includes an internalangular surface 103 adjoining the end face 84 b thereof.

A pair of hinge blocks 104 a and 104 b are connected to the annular body84 at the end face 84 b thereof. In several example embodiments, thehinge blocks 104 a and 104 b are integrally formed with the annular body84. The hinge blocks 104 a and 104 b are disposed at or near theopposing end portions 100 a and 100 b, respectively, of the wall portion100. Moreover, the hinge blocks 104 a and 104 b each include a curvedexternal surface 106 that is substantially aligned with an externalsurface of the annular body 84 and a curved interior surface 108 that issubstantially aligned with an interior surface of the annular body 84.As a result, the hinge blocks 104 a and 104 b are spaced apart from oneanother by the central opening 88 of the annular body 84.

A tapered slot 110 is formed through each of the hinge blocks 104 a and104 b. The tapered slots 110 each include opposing end portions 110 aand 110 b. The end portions 110 a of the tapered slots 110 each definean internal dimension D1 that is relatively smaller than an internaldimension D2 defined by the end portions 110 b. As a result, when theclapper 18 is in the open configuration, one or more componentsassociated with the clapper 18 are not permitted vertical clearancewithin the hinge blocks 104 a and 104 b at the end portions 110 a of thetapered slots 110, as will be discussed in further detail below.Moreover, forces imparted on the clapper 18 (or portions thereof) by,for example, fluid flow through the inlet passageway 34, the fluidpassageway 64, and the internal region 32 prevent, or at least reduce,horizontal movement of the one or more components associated with theclapper 18 within the hinge blocks 104 a and 104 b at the end portions110 a of the tapered slots 110. In contrast, the internal dimension D2defined by the end portions 110 b of the tapered slots 110 is relativelylarger than the internal dimension D1 defined by the end portions 110 a.As a result, when the clapper 18 is in the closed configuration, one ormore components associated with the clapper 18 are permitted verticalclearance within the hinge blocks 104 a and 104 b at the end portions110 b of the tapered slots 110, as will be discussed in further detailbelow. In several example embodiments, the hinge blocks 104 a and 104 bare oriented such that the tapered slots 110 are substantially alignedwith one another.

Referring to FIGS. 3A-3D, with continuing reference to FIGS. 1A and 1B,an example embodiment of the clapper 18 is illustrated. The clapper 18includes a generally disk-shaped valve member 112 extending about acentral axis 114. The valve member 112 includes acircumferentially-extending exterior surface 116 situated axiallybetween a pair of opposing end faces 112 a and 112 b. The exteriorsurface 116 delineates the outer periphery of the valve member 112. Inseveral example embodiments, at least a portion of the exterior surface116 defines a generally curved profile. The valve member 112 furtherincludes an external angular surface 118 adjoining the end face 112 aand the exterior surface 116.

An external annular groove 120 is formed in the end face 112 b and theexterior surface 116 of the valve member 112. The external annulargroove 120 includes a concave surface 122 and a pair of annular rounds124 a and 124 b in the valve member 112. The annular round 124 a adjoinsthe exterior surface 116 of the valve member 112. In several exampleembodiments, the annular round 124 a is axially offset from the end face112 b of the valve member 112. Similarly, the annular round 124 badjoins the end face 112 b of the valve member 112. In several exampleembodiments, the annular round 124 b is radially offset from theexterior surface 116 of the valve member 112. The concave surface 122adjoins each of the annular rounds 124 a and 124 b.

A seal 126 extends within the external annular groove 120 and includes acircumferentially-extending exterior surface 128 extending adjacent theexterior surface 116 of the valve member 112. The seal 126 includes anannular concave surface 130, an annular bulbous protrusion 132, anannular contact surface 134, and an annular tapered surface 136. Theconcave surface 130 is formed axially between the exterior surface 116of the valve member 112 and the bulbous protrusion 132 of the seal 126.In several example embodiments, the bulbous protrusion 132 is situatedadjacent the concave surface 130. The contact surface 134 extendsradially inward from the bulbous protrusion 132 and is adapted tosealingly engage the end face 14 a of the valve seat 14 when the clapper18 is in the closed configuration, as will be discussed in furtherdetail below. In several example embodiments, the contact surface 134 isaxially offset from the end face 112 b of the valve member 112. Thetapered surface 136 extends inward from the contact surface 134, theextension of the tapered surface 136 ending at, or proximate, the endface 112 b of the valve member 112.

A hinge block 138 is connected to the valve member 112 at the end face112 a thereof. In several example embodiments, the hinge block 138 isintegrally formed with the valve member 112. The hinge block 138includes a proximal end portion 138 a, located at or near the centralaxis 114 of the valve member 112, and a distal end portion 138 b,extending radially beyond the exterior surface 116 of the valve member112. A generally cylindrical passage 140 is formed through the hingeblock 138 proximate the distal end portion 138 b thereof. In severalexample embodiments, the cylindrical passage 140 extends perpendicularto, or substantially perpendicular to, a radial line intersecting thecentral axis 114 of the valve member 112. The hinge block 138 is adaptedto extend between the hinge blocks 104 a and 104 b of the hanger 16 sothat the cylindrical passage 140 of the clapper 18 is substantiallyaligned with the tapered slots 110 of the hanger 16.

In several example embodiments, the extension of the seal 126 within theexternal annular groove 120 facilitates the securing of the seal 126 tovalve member 112. In several example embodiments, the seal 126 is bondedto the concave surface 122 and the annular rounds 124 a and 124 b of thevalve member 112. In several example embodiments, the seal 126 is aunitary structure and thus the exterior surface 128, the concave surface130, the bulbous protrusion 132, the contact surface 134, and thetapered surface 136, as well as the respective portions of the seal 126extending within the external annular groove 120, are integrally formed.

In several example embodiments, the seal 126 is composed ofpolyurethane. In several example embodiments, the seal 126 is a unitarystructure of polyurethane, and thus the exterior surface 128, theconcave surface 130, the bulbous protrusion 132, the contact surface134, and the tapered surface 136, as well as the respective portions ofthe seal 126 extending within the external annular groove 120, areintegrally formed using polyurethane. In several example embodiments,the seal 126 is composed of polyurethane that is bonded to the concavesurface 122 and the annular rounds 124 a and 124 b of the valve member112, thus preventing, or at least reducing, damage and/or washout of theseal 126 in the presence of hard abrasive fluids (i.e., sand, chemicals,proppant, or the like).

In an example embodiment, the seal 126 is molded in place in the valvemember 112. In an example embodiment, the seal 126 is pre-formed andthen attached to the valve member 112. In several example embodiments,the seal 126 is composed of one or more materials such as, for example,a deformable thermoplastic material, a polyurethane material, afiber-reinforced material, carbon, glass, cotton, wire fibers, cloth,and/or any combination thereof. In an example embodiment, the seal 126is composed of a cloth which is disposed in a thermoplastic material,and the cloth may include carbon, glass, wire, cotton fibers, and/or anycombination thereof. In several example embodiments, the seal 126 iscomposed of at least a fiber-reinforced material, which can prevent orat least reduce delamination. In several example embodiments, the valvemember 112 is much harder and more rigid than the seal 126.

Referring now to FIGS. 4A-4C, the clapper valve 10 is illustrated in anassembled state, including the valve body 12, the valve seat 14, thehanger 16, the clapper 18, and the cap 20, according to an exampleembodiment.

In the assembled state, as shown most clearly in FIG. 4A, the valve seat14 extends within and engages the valve body 12. More particularly, theexternal threaded connection 74 of the valve seat 14 threadably engagesthe internal threaded connection 46 of the valve body 12. As a result,the external shoulder 70 of the valve seat 14 engages the internalshoulder 40 of the valve body 12. In this position, the end face 14 b ofthe valve seat 14 abuts, or nearly abuts, the counterbore shoulder 44 ofthe valve body 12. One or more set screws 142 are engaged (threadably orotherwise) with the valve body 12 at the one or more openings 62 in theledge 58. Moreover, the external annular recess 72 is aligned with theone or more openings 62 in the ledge 58. As a result, the set screws 142extend through the openings 62 and into the external annular recess 72,thus preventing, or at least discouraging, the external threadedconnection 74 from disengaging the internal threaded connection 46.

In several example embodiments, an annular seal 144 extends within theexternal annular groove 76 of the valve seat 14 and sealingly engagesthe cylindrical surface 48 of the valve body 12. In an alternativeembodiment, the external annular groove 76 of the valve seat 14 isomitted or replaced by an annular groove (not shown) in which theannular seal 144 extends, which annular groove is formed in thecylindrical surface 48 of the valve body 12. In another alternativeembodiment, the annular groove is formed in the end face 14 b of thevalve seat 14. In yet another alternative embodiment, the annular grooveis formed in the counterbore shoulder 44 of the valve body 12.

The annular seal 144 is configured to reduce a force imparted on theannular seal 144 when relative motion is effected between the valve seat14 and the valve body 12. More particularly, in several exampleembodiments, the annular seal 144 is a twist-resistant seal that fitswithin the external annular groove 76 (or, when the annular groove 76 isomitted, another annular groove) to prevent, or at least reduce,distortion of the annular seal 144 when the external threaded connection74 is threadably engaged with the internal threaded connection 46. Forexample, the distortion of the annular seal 144 may be prevented, or atleast reduced, by providing a twist-resistant seal that facilitatesface-to-face contact (rather than point contact) between the annularseal 144 and the cylindrical surface 48 (or between the annular seal 144and the counterbore shoulder 44). In several exemplary embodiments, topromote said face-to-face contact between the annular seal 144 and thecylindrical surface 48, the annular seal 144 includes a sealing face(e.g., cylindrical or disk-shaped) extending substantially parallel tothe portion of the valve body 12 with which the annular seal 144 isadapted to be sealingly engaged (e.g., the cylindrical surface 48 or thecounterbore shoulder 44). In several exemplary embodiments, the annularseal 144 has a rectangular cross-section that promotes said face-to-facecontact between the annular seal 144 and the cylindrical surface 48.

Further, as shown most clearly in FIG. 4B, the hanger 16 extends withinthe access bore 50 of the valve body 12. Moreover, the external threadedconnection 78 (visible in FIG. 4A) of the cap 20 is threadably engagedwith the internal threaded connection 54 (visible in FIG. 4A) of thevalve body 12. As a result, the end portion 20 b of the cap 20 abuts, ornearly abuts, the end face 84 a of the hanger 16, thus causing theexternal lip 89 of the hanger 16 to engage, or nearly engage, theinternal shoulder 56 of the valve body 12. In this manner, the cap 20secures the hanger 16 within the valve body 12 and causes the segment 94of the hanger 16 (which has approximately the same radial dimension andshape as the ledge 58 of the valve body 12) to abut, or nearly abut, theledge 58 of the valve body 12. In this position, the wall portion 100 ofthe hanger 16 engages the edge 60 of the ledge 58 to act as ananti-rotation device for the hanger 16 within the valve body 12.

In several example embodiments, an annular seal 146 is accommodatedwithin the external annular groove 82 of the cap 20. The annular seal146 sealingly engages the cylindrical surface 57 of the valve body 12,thus preventing, or at least reducing, leakage of a fluid from theinterior of the clapper valve 10 to atmosphere. In several exampleembodiments, a backup ring 148 is also accommodated within the externalannular groove 82 of the cap 20 to prevent, or at least reduce,extrusion of the annular seal 146.

In several example embodiments, a biasing member 150 is constrainedbetween the external shoulder 102 of the hanger 16 and the end portion20 b of the cap 20. In this position, the biasing member 150 urges theexternal lip 89 of the hanger 16 into engagement, or near engagement,with the internal shoulder 56 of the valve body 12. In an exampleembodiment, the biasing member 150 is a wave spring. In several exampleembodiments, the biasing member 150 is, includes, or is part of one ormore components that are not a wave spring, such as, for example, aBelleville washer, a helical spring, a compressed elastic material,another type of biasing member, or any combination thereof. In thismanner, the cap 20 and the biasing member 150 together act to secure thehanger 16 within the valve body 12. Moreover, the engagement, or nearengagement, between the external lip 89 of the hanger 16 and theinternal shoulder 56 of the valve body 12 causes the hinge blocks 104 aand 104 b of the hanger 16 to extend within the internal region 32 ofthe valve body 12. In several example embodiments, despite the thermalexpansion or contraction of the various components of the clapper valve10 during operation, the biasing member 150 maintains the engagement, ornear engagement between the external lip 89 of the hanger 16 and theinternal shoulder 56 of the valve body 12.

Further still, as shown most clearly in FIG. 4C, the clapper 18 extendswithin the internal region 32 of the valve body 12. More particularly,the hinge block 138 of the clapper 18 extends between the hinge blocks104 a and 104 b of the hanger 16. As a result, the cylindrical passage140 of the clapper 18 is substantially aligned with the tapered slots110 of the hanger 16. A pin 152 extends within the cylindrical passage140 of the clapper 18 and the tapered slots 110 of the hanger 16, thuspivotably connecting the clapper 18 to the hanger 16. In this position,the clapper 18 is actuable between the open configuration (shown in FIG.5A; discussed in detail below), in which fluid flow is permitted throughthe valve body 12, and the closed configuration (shown in FIGS. 4C and6A; discussed in detail below), in which the clapper 18 is seatedagainst the valve seat 14 to at least partially restrict fluid flowthrough the valve body 12.

In some example embodiments, as illustrated in FIGS. 5A, 5B, 6A, and 6B,a fluid 154 flows through the clapper valve 10 and actuates the clapper18 between the open configuration and the closed configuration. Thevalve body 12 is omitted from FIGS. 5A, 5B, 6A, and 6B to more clearlydepict the valve seat 14, the hanger 16, the clapper 18, and the cap 20(in the assembled state). However, even though the valve body 12 is notshown in FIGS. 5A, 5B, 6A, and 6B, several components of the valve body12 will be discussed (using the above-mentioned reference numerals)hereinbelow as necessary to describe the operation of the clapper valve10.

In the open configuration, as shown in FIGS. 5A and 5B, with continuingreference to FIGS. 4A-4C, the fluid 154 flows into the inlet passageway34, through the internal region 32, and exits the outlet passageway 36,thus causing the clapper 18 to pivot about the pin 152 in an angulardirection 156. As the clapper 18 pivots about the pin 152 in the angulardirection 156, the pin 152 is urged (from right to left as viewed inFIGS. 5A and 5B) toward the respective end portions 110 a of the taperedslots 110. The pin 152 is not permitted vertical clearance within thehinge blocks 104 a and 104 b at the end portions 110 a of the slots 110(i.e., the internal dimension D1 of the end portions 110 a is relativelysmaller than the internal dimension D2 of the end portions 110 b).Moreover, forces imparted on the clapper 18 (or portions thereof) by,for example, fluid flow through the inlet passageway 34, the fluidpassageway 64, and the internal region 32 prevent, or at least reduce,horizontal movement of the pin 152 within the hinge blocks 104 a and 104b at the end portions 110 a of the tapered slots 110. As the clapper 18continues to pivot about the pin 152 in the angular direction 156, theclapper 18 abuts, or nearly abuts, the valve body 12 such that theclapper 18 is prevented from further pivoting in the angular direction156. In several example embodiments, when the clapper 18 is in the openconfiguration, the tightened vertical clearance between the pin 152 andthe hinge blocks 104 a and 104 b at the end portions 110 a of thetapered slots 110 prevents, or at least reduces, any wear and/orvibration of the hanger 16 and/or the clapper 18 that is caused by, forexample, turbulence in the fluid 154. Similarly, the prevention, or atleast reduction, of horizontal movement of the pin 152 when the clapper18 is in the open configuration prevents, or at least reduces, any wearand/or vibration of the hanger 16 and/or the clapper 18 that is causedby, for example, turbulence in the fluid 154.

In the closed configuration, as shown in FIGS. 6A and 6B, withcontinuing reference to FIGS. 4A-4C, the flow of the fluid 154 isreversed so that the fluid 154 flows through the outlet passageway 36and into the internal region 32, thus causing the clapper 18 to pivotabout the pin 152 in an angular direction 158, which is opposite theangular direction 156. As the clapper 18 pivots about the pin 152 in theangular direction 158, the pin 152 is urged (from left to right asviewed in FIGS. 6A and 6B) toward the respective end portions 110 b ofthe tapered slots 110. The pin 152 is permitted vertical clearancewithin the hinge blocks 104 a and 104 b at the end portions 110 b of theslots 110 (i.e., the internal dimension D2 of the end portions 110 b isrelatively larger than the internal dimension D1 of the end portions 110a). As the clapper 18 continues to pivot about the pin 152 in theangular direction 158, the contact surface 134 of the seal 126 sealinglyengages the end face 14 a of the valve seat 14. The seal 126 iscompressed against the end face 14 a and expands radially outward (asshown in FIG. 4C) until the end face 112 b of the clapper 18 contactsthe end face 14 a of the valve seat 14, thus establishing a “hard stop”and limiting further compression of the seal 126. In several exampleembodiments, the “hard stop” between the end face 112 b of the clapper18 and the end face 14 a of the valve seat 14 prevents, or at leastreduces, overloading of the seal 126.

In several example embodiments, the sealing engagement of the seal 126on the valve seat 14 is facilitated by the vertical and/or horizontalclearance between the pin 152 and the hinge blocks 104 a and 104 b atthe end portions 110 b of the slots 110. More particularly, the verticaland/or horizontal clearance between the pin 152 and the hinge blocks 104a and 104 b at the end portions 110 b of the slots 110 allows the seal126 to seat evenly on the valve seat 14 so that the force imparted tothe clapper 18 by the fluid 154 is evenly distributed on the seal 126and the valve seat 14, as shown in FIG. 4C.

In several example embodiments, the “hard stop” between the clapper 18and the valve seat 14 is facilitated by the vertical and/or horizontalclearance between the pin 152 and the hinge blocks 104 a and 104 b atthe end portions 110 b of the slots 110. More particularly, the verticaland/or horizontal clearance between the pin 152 and the hinge blocks 104a and 104 b at the end portions 110 b of the slots 110 allows the endface 112 b of the clapper 18 to seat evenly on the end face 14 a of thevalve seat 14 so that the force imparted to the clapper 18 by the fluid154 is evenly distributed on the respective end faces 112 b and 14 a, asshown in FIG. 4C.

In several example embodiments, the axial offset of the annular round124 a from the end face 112 b of the valve member 112 permits theradially outward expansion of the seal 126 beyond the exterior surface116 of the valve member 112. In several example embodiments, the axialoffset of the annular round 124 a from the end face 112 b of the valvemember 112 prevents, or at least reduces, radially inward expansion ofthe seal 126 into the space between the end face 112 b and the valveseat 14 (i.e., the area where the “hard stop” is established). Inseveral example embodiments, the axial offset of the annular round 124 afrom the end face 112 b of the valve member 112 prevents, or at leastreduces, overloading of the seal 126.

In several example embodiments, the radial offset of the annular round124 b from the exterior surface 116 of the valve member 112 permits thecontact surface 134 of the seal 126 to extend axially beyond the endface 112 b of the valve member 112. In several example embodiments, theradial offset of the annular round 124 b from the exterior surface 116of the valve member 112 permits engagement between the seal 126 and thevalve seat 14 before the end face 112 b engages the valve seat 14. Inseveral example embodiments, the radial offset of the annular round 124b from the exterior surface 116 of the valve member 112 permits properloading of the seal 126.

In several example embodiments, the shape or profile of the seal 126permits the radially outward expansion of the seal 126 beyond theexterior surface 116 of the valve member 112. In several exampleembodiments, the shape or profile of the seal 126 prevents, or at leastreduces, radially inward expansion of the seal 126 into the spacebetween the end face 112 b and the valve seat 14 (i.e., the area wherethe “hard stop” is established). In several example embodiments, theshape or profile of the seal 126 prevents, or at least reduces,overloading of the seal 126.

In several example embodiments, the biasing member 150 prevents, or atleast reduces, wear and vibration of the hanger 16 and or the clapper 18caused by, for example, turbulence in the fluid 154. In several exampleembodiments, the biasing member 150 permits flexibility of dimensionaltolerances between various components of the clapper valve 10. Inseveral example embodiments, the biasing member 150 reduces rigiditybetween various components of the clapper valve 10.

It is understood that variations may be made in the foregoing withoutdeparting from the scope of the present disclosure.

In several example embodiments, the elements and teachings of thevarious illustrative example embodiments may be combined in whole or inpart in some or all of the illustrative example embodiments. Inaddition, one or more of the elements and teachings of the variousillustrative example embodiments may be omitted, at least in part,and/or combined, at least in part, with one or more of the otherelements and teachings of the various illustrative embodiments.

Any spatial references, such as, for example, “upper,” “lower,” “above,”“below,” “between,” “bottom,” “vertical,” “horizontal,” “angular,”“upwards,” “downwards,” “side-to-side,” “left-to-right,”“right-to-left,” “top-to-bottom,” “bottom-to-top,” “top,” “bottom,”“bottom-up,” “top-down,” etc., are for the purpose of illustration onlyand do not limit the specific orientation or location of the structuredescribed above.

In several example embodiments, while different steps, processes, andprocedures are described as appearing as distinct acts, one or more ofthe steps, one or more of the processes, and/or one or more of theprocedures may also be performed in different orders, simultaneouslyand/or sequentially. In several example embodiments, the steps,processes, and/or procedures may be merged into one or more steps,processes and/or procedures.

In several example embodiments, one or more of the operational steps ineach embodiment may be omitted. Moreover, in some instances, somefeatures of the present disclosure may be employed without acorresponding use of the other features. Moreover, one or more of theabove-described embodiments and/or variations may be combined in wholeor in part with any one or more of the other above-described embodimentsand/or variations.

Although several example embodiments have been described in detailabove, the embodiments described are exemplary only and are notlimiting, and those skilled in the art will readily appreciate that manyother modifications, changes and/or substitutions are possible in theexample embodiments without materially departing from the novelteachings and advantages of the present disclosure. Accordingly, allsuch modifications, changes, and/or substitutions are intended to beincluded within the scope of this disclosure as defined in the followingclaims. In the claims, any means-plus-function clauses are intended tocover the structures described herein as performing the recited functionand not only structural equivalents, but also equivalent structures.Moreover, it is the express intention of the applicant not to invoke 35U.S.C. § 112, paragraph 6 for any limitations of any of the claimsherein, except for those in which the claim expressly uses the word“means” together with an associated function.

What is claimed is:
 1. A valve assembly, comprising: a valve bodydefining an internal region, an inlet passageway, and an outletpassageway, the inlet and outlet passageways extending into the internalregion; a valve seat connected to the valve body and defining a fluidpassageway, the valve seat comprising a first end face extending aboutthe fluid passageway; a clapper extending within the internal region,the clapper comprising: a second end face into which a first annulargroove is formed; and a circumferentially-extending exterior surfaceinto which the first annular groove is formed, thecircumferentially-extending exterior surface having a nonparallelrelation with the second end face; a seal extending within the firstannular groove and adapted to sealingly engage the first end face of thevalve seat; wherein the clapper is actuable between: an openconfiguration, in which fluid flow is permitted through the fluidpassageway; and a closed configuration, in which the seal sealinglyengages the first end face to at least partially restrict fluid flowthrough the fluid passageway; and wherein the seal comprises aradially-extending contact surface adapted to contact the first end facewhen the clapper is in the closed configuration, the radially-extendingcontact surface being axially offset from the second end face.
 2. Thevalve assembly of claim 1, wherein, when the clapper is in the closedconfiguration, the second end face contacts the first end face to limitcompression of the seal against the first end face.
 3. The valveassembly of claim 1, wherein the seal further comprises an annularbulbous protrusion.
 4. The valve assembly of claim 1, wherein, at thefirst annular groove, the clapper comprises first and second annularrounds and a concave surface, the first annular round adjoining theexterior surface and being axially offset from the second end face topermit radial expansion of the seal, the second annular round adjoiningthe second end face, and the concave surface adjoining the first andsecond annular rounds.
 5. The valve assembly of claim 1, wherein thevalve body further defines an access bore extending into the internalregion; and wherein the valve assembly further comprises a hangerextending within the access bore, the clapper being pivotably coupled tothe hanger so as to be pivotable between the open configuration and theclosed configuration.
 6. The valve assembly of claim 5, wherein thehanger defines first and second tapered slots, the first tapered slotdefining first and second end portions, the second tapered slot definingthird and fourth end portions, the first and third end portions eachhaving a first internal dimension, and the second and fourth endportions each having a second internal dimension, wherein the firstinternal dimension is less than the second internal dimension.
 7. Thevalve assembly of clam 6, wherein the hanger comprises first and secondhinge blocks, the first tapered slot being formed in the first hingeblock, and the second tapered slot being formed in the second hingeblock; wherein the clapper comprises a third hinge block extendingbetween the first and second hinge blocks, the third hinge blockdefining a cylindrical passage; and wherein the valve assembly furthercomprises a pin extending within the first and second tapered slots andthe cylindrical passage.
 8. The valve assembly of claim 7, wherein, whenthe clapper is in the open configuration, the pin is urged toward thefirst and third end portions of the first and second tapered slots,respectively, such that the pin is at least partially restricted frommoving one or more of vertically or horizontally relative to the hanger.9. The valve assembly of claim 6, wherein, when the clapper is in theclosed configuration, the pin is urged toward the second and fourth endportions of the first and second tapered slots, respectively, to enablethe pin to at least partially move one or more of vertically orhorizontally relative to the hanger.
 10. The valve assembly of claim 5,wherein the valve body comprises an internal shoulder at the accessbore; and wherein the valve assembly further comprises a cap coupled tothe valve body at the access bore and a biasing member positionedbetween the cap and the hanger, the biasing member urging the hangertowards the internal shoulder of the valve body.
 11. The valve assemblyof claim 1, wherein the valve body further defines a counterbore and thevalve seat further defines a second annular groove, the valve seat beingadapted to be removably engaged with the valve body at the counterbore;and wherein an annular seal extends within the second annular groove andis adapted to sealingly engage a portion of the valve body when thevalve seat is removably engaged with the valve body, the annular sealbeing configured to reduce a force imparted on the annular seal whenrelative motion is effected between the valve seat and the valve body.12. The valve assembly of claim 11, wherein, to promote face-to-facecontact between the annular seal and the valve body, the annular sealincludes a sealing face extending substantially parallel to the portionof the valve body with which the annular seal is adapted to be sealinglyengaged.
 13. A valve member adapted to be seated against a valve seatthat defines a fluid passageway, the valve member comprising: a body,comprising: an end face into which an annular groove is formed; and acircumferentially-extending exterior surface into which the annulargroove is formed, the circumferentially-extending exterior surfacehaving a nonparallel relation with the end face; and a seal extendingwithin the annular groove of the body and adapted to sealingly engagethe valve seat; wherein the valve member is actuable between: an openconfiguration, in which fluid flow is permitted through the fluidpassageway; and a closed configuration, in which the seal sealinglyengages the valve seat to at least partially restrict fluid flow throughthe fluid passageway; and wherein the seal comprises aradially-extending contact surface adapted to contact the valve seatwhen the valve member is in the closed configuration, theradially-extending contact surface being axially offset from the endface.
 14. The valve member of claim 13, wherein, when the valve memberis in the closed configuration, the end face contacts the valve seat tolimit compression of the seal against the valve seat.
 15. The valvemember of claim 13, wherein the seal further comprises an annularbulbous protrusion.
 16. The valve member of claim 15, wherein the sealfurther comprises an annular concave surface axially between theexterior surface of the valve member and the annular bulbous protrusion.17. The valve member of claim 13, wherein, at the annular groove, thebody comprises first and second annular rounds and a concave surface,the first annular round adjoining the exterior surface, the secondannular round adjoining the end face, and the concave surface adjoiningthe first and second annular rounds.
 18. The valve member of claim 17,wherein the first annular round is axially offset from the end face topermit radial expansion of the seal.
 19. A valve assembly, comprising: avalve body defining an internal region, an inlet passageway, and anoutlet passageway, the inlet and outlet passageways extending into theinternal region; a valve seat connected to the valve body and defining afluid passageway, the valve seat comprising a first end face extendingabout the fluid passageway; a clapper extending within the internalregion, the clapper comprising a second end face at least partiallydefining a first annular groove; and a seal extending within the firstannular groove and adapted to sealingly engage the first end face of thevalve seat; wherein the clapper is actuable between: an openconfiguration, in which fluid flow is permitted through the fluidpassageway; and a closed configuration, in which the seal sealinglyengages the first end face to at least partially restrict fluid flowthrough the fluid passageway wherein the clapper further comprises acircumferentially-extending exterior surface at least partially definingthe first annular groove; and wherein the seal comprises an annularbulbous protrusion and a radially-extending contact surface adapted tocontact the first end face when the clapper is in the closedconfiguration, the radially-extending contact surface being axiallyoffset from the second end face.
 20. The valve assembly of claim 19,wherein, when the clapper is in the closed configuration, the second endface contacts the first end face to limit compression of the sealagainst the first end face.
 21. The valve assembly of claim 19, whereinthe valve body further defines a counterbore and the valve seat furtherdefines a second annular groove, the valve seat being adapted to beremovably engaged with the valve body at the counterbore; and wherein anannular seal extends within the second annular groove and is adapted tosealingly engage a portion of the valve body when the valve seat isremovably engaged with the valve body, the annular seal being configuredto reduce a force imparted on the annular seal when relative motion iseffected between the valve seat and the valve body.
 22. The valveassembly of claim 21, wherein, to promote face-to-face contact betweenthe annular seal and the valve body, the annular seal includes a sealingface extending substantially parallel to the portion of the valve bodywith which the annular seal is adapted to be sealingly engaged.
 23. Avalve assembly, comprising: a valve body defining an internal region, aninlet passageway, and an outlet passageway, the inlet and outletpassageways extending into the internal region; a valve seat connectedto the valve body and defining a fluid passageway, the valve seatcomprising a first end face extending about the fluid passageway; aclapper extending within the internal region, the clapper comprising asecond end face at least partially defining a first annular groove; anda seal extending within the first annular groove and adapted tosealingly engage the first end face of the valve seat; wherein theclapper is actuable between: an open configuration, in which fluid flowis permitted through the fluid passageway; and a closed configuration,in which the seal sealingly engages the first end face to at leastpartially restrict fluid flow through the fluid passageway wherein theclapper further comprises a circumferentially-extending exterior surfaceat least partially defining the first annular groove; and wherein, atthe first annular groove, the clapper comprises first and second annularrounds and a concave surface, the first annular round adjoining theexterior surface and being axially offset from the second end face topermit radial expansion of the seal, the second annular round adjoiningthe second end face, and the concave surface adjoining the first andsecond annular rounds.
 24. The valve assembly of claim 23, wherein, whenthe clapper is in the closed configuration, the second end face contactsthe first end face to limit compression of the seal against the firstend face.
 25. The valve assembly of claim 23, wherein the valve bodyfurther defines a counterbore and the valve seat further defines asecond annular groove, the valve seat being adapted to be removablyengaged with the valve body at the counterbore; and wherein an annularseal extends within the second annular groove and is adapted tosealingly engage a portion of the valve body when the valve seat isremovably engaged with the valve body, the annular seal being configuredto reduce a force imparted on the annular seal when relative motion iseffected between the valve seat and the valve body.
 26. The valveassembly of claim 25, wherein, to promote face-to-face contact betweenthe annular seal and the valve body, the annular seal includes a sealingface extending substantially parallel to the portion of the valve bodywith which the annular seal is adapted to be sealingly engaged.
 27. Avalve assembly, comprising: a valve body defining an internal region, aninlet passageway, and an outlet passageway, the inlet and outletpassageways extending into the internal region; a valve seat connectedto the valve body and defining a fluid passageway, the valve seatcomprising a first end face extending about the fluid passageway; aclapper extending within the internal region, the clapper comprising asecond end face at least partially defining a first annular groove; anda seal extending within the first annular groove and adapted tosealingly engage the first end face of the valve seat; wherein theclapper is actuable between: an open configuration, in which fluid flowis permitted through the fluid passageway; and a closed configuration,in which the seal sealingly engages the first end face to at leastpartially restrict fluid flow through the fluid passageway; wherein thevalve body further defines an access bore extending into the internalregion; and wherein the valve assembly further comprises a hangerextending within the access bore, the clapper being pivotably coupled tothe hanger so as to be pivotable between the open configuration and theclosed configuration; and wherein the hanger defines first and secondtapered slots, the first tapered slot defining first and second endportions, the second tapered slot defining third and fourth endportions, the first and third end portions each having a first internaldimension, and the second and fourth end portions each having a secondinternal dimension, wherein the first internal dimension is less thanthe second internal dimension.
 28. The valve assembly of clam 27,wherein the hanger comprises first and second hinge blocks, the firsttapered slot being formed in the first hinge block, and the secondtapered slot being formed in the second hinge block; wherein the clappercomprises a third hinge block extending between the first and secondhinge blocks, the third hinge block defining a cylindrical passage; andwherein the valve assembly further comprises a pin extending within thefirst and second tapered slots and the cylindrical passage.
 29. Thevalve assembly of claim 28, wherein, when the clapper is in the openconfiguration, the pin is urged toward the first and third end portionsof the first and second tapered slots, respectively, such that the pinis at least partially restricted from moving one or more of verticallyor horizontally relative to the hanger.
 30. The valve assembly of claim27, wherein, when the clapper is in the closed configuration, the pin isurged toward the second and fourth end portions of the first and secondtapered slots, respectively, to enable the pin to at least partiallymove one or more of vertically or horizontally relative to the hanger.31. The valve assembly of claim 27, wherein the valve body comprises aninternal shoulder at the access bore; and wherein the valve assemblyfurther comprises a cap coupled to the valve body at the access bore anda biasing member positioned between the cap and the hanger, the biasingmember urging the hanger towards the internal shoulder of the valvebody.
 32. The valve assembly of claim 27, wherein, when the clapper isin the closed configuration, the second end face contacts the first endface to limit compression of the seal against the first end face. 33.The valve assembly of claim 27, wherein the valve body further defines acounterbore and the valve seat further defines a second annular groove,the valve seat being adapted to be removably engaged with the valve bodyat the counterbore; and wherein an annular seal extends within thesecond annular groove and is adapted to sealingly engage a portion ofthe valve body when the valve seat is removably engaged with the valvebody, the annular seal being configured to reduce a force imparted onthe annular seal when relative motion is effected between the valve seatand the valve body.
 34. The valve assembly of claim 33, wherein, topromote face-to-face contact between the annular seal and the valvebody, the annular seal includes a sealing face extending substantiallyparallel to the portion of the valve body with which the annular seal isadapted to be sealingly engaged.
 35. A valve member adapted to be seatedagainst a valve seat that defines a fluid passageway, the valve membercomprising: a body comprising an end face at least partially defining anannular groove; and a seal extending within the annular groove of thebody and adapted to sealingly engage the valve seat; wherein the valvemember is actuable between: an open configuration, in which fluid flowis permitted through the fluid passageway; and a closed configuration,in which the seal sealingly engages the valve seat to at least partiallyrestrict fluid flow through the fluid passageway wherein the bodyfurther comprises a circumferentially-extending exterior surface atleast partially defining the annular groove; and wherein the sealcomprises an annular bulbous protrusion and a radially-extending contactsurface adapted to contact the valve seat when the valve member is inthe closed configuration, the radially-extending contact surface beingaxially offset from the end face.
 36. The valve member of claim 35,wherein the seal further comprises an annular concave surface axiallybetween the exterior surface of the valve member and the annular bulbousprotrusion.
 37. The valve member of claim 35, wherein, when the valvemember is in the closed configuration, the end face contacts the valveseat to limit compression of the seal against the valve seat.
 38. Avalve member adapted to be seated against a valve seat that defines afluid passageway, the valve member comprising: a body comprising an endface at least partially defining an annular groove; and a seal extendingwithin the annular groove of the body and adapted to sealingly engagethe valve seat; wherein the valve member is actuable between: an openconfiguration, in which fluid flow is permitted through the fluidpassageway; and a closed configuration, in which the seal sealinglyengages the valve seat to at least partially restrict fluid flow throughthe fluid passageway wherein the body further comprises acircumferentially-extending exterior surface at least partially definingthe annular groove; and wherein, at the annular groove, the bodycomprises first and second annular rounds and a concave surface, thefirst annular round adjoining the exterior surface, the second annularround adjoining the end face, and the concave surface adjoining thefirst and second annular rounds.
 39. The valve member of claim 38,wherein the first annular round is axially offset from the end face topermit radial expansion of the seal.
 40. The valve member of claim 38,wherein, when the valve member is in the closed configuration, the endface contacts the valve seat to limit compression of the seal againstthe valve seat.